A kind of frequency conversion type constant-pressure water feeding system control system and method
Technical field
The present invention relates to a kind of frequency conversion type constant-pressure water feeding system control system and method, belong to automatic control technology field.
Background technology
With developing rapidly for society, city is constantly extended, and urban population is continuously increased, and town dweller's water consumption is significantly more
Plus, great pressure is brought to waterworks, according to used water system situation, the automation journey that there is currently for water factory
Degree is not high, and energy consumption is larger, and to meet the life use of growing number of resident, original old equipment of running water transport by excess load
Make, the situation that reliability is greatly reduced, while being difficult to ensure that the stability of water supply with the peak period of water.As people are to supplying
The increasingly raising of water requirement, with reference to the rapid constant pressure water supply technology of Developing and Field Bus Control Technology, to sending water
Pumping plant, which is monitored, to be realized constant pressure water supply and whole waterworks field apparatus is carried out to monitor in real time and real-time data acquisition.Cause
This must be just transformed the correlation technique of water factory, with realize supply water efficiently, stably, reliable purpose.Realize permanent to user
Pressure supplies water turns into the inevitable choice of Running-water Company, and simultaneity factor needs to adapt to ever-increasing supply equipment access.
The content of the invention
The invention provides a kind of frequency conversion type constant-pressure water feeding system control system and method, for solving existing city dweller
Rapidly increase the problem of difficult water supply brought and unstable water supply, old supply equipment is supplied in the peak period of resident and low peak period
Water mode is unalterable so that hydraulic pressure deficiency occurs in peak period, and low peak period hydraulic pressure is excessive, it is impossible to ensures constant pressure water supply, makes simultaneously
The problem of into power resource serious waste.
The technical scheme is that:A kind of frequency conversion type constant-pressure water feeding system control system, including PLC1, frequency converter 2, liquid
Level sensor 3, analog output module 4, pressure sensor 5, contactor switching circuit 6, water pump 7, motor 8, mould is controlled manually
Block 9;
The analog output module 4, frequency converter 2 and manual control module 9 are connected with PLC1 respectively, liquid level sensor
3 detection output signals be connected with analog output module 4, pressure sensor 5 detection output signal respectively with analog quantity
Output module 4 is connected with the PID modules of frequency converter 2, and the PID modules of PLC1 and frequency converter 2 are connected respectively to contactor switching
Circuit 6, contactor switching circuit 6 is connected with motor 8, and motor 8 drives the operating of water pump 7 to supply water.
Also include PROFIBUS fieldbus 10 and PC Monitor Computer Control Systems 11;Wherein, PC Monitor Computer Control Systems 11
It is connected by PROFIBUS fieldbus 10 with PLC1.
A kind of frequency conversion type constant-pressure water feeding system control method, methods described is comprised the following steps that:
Step1, the interval of pipe pressure parameter objectives value is set by PLC1 as [0.95SP, 1.05SP];
Step2, judge manual mode or automatic mode operation:
Step2.1, if manual mode, then start manual handle module 9:PLC1 detects liquid level sensor 3 whether there is
Water-level alarm signal;If water-level alarm signal, then termination of pumping control is carried out, if without water level alarm signal, detecting pressure
Sensor 5 whether there is superpressure signal;If superpressure signal, then termination of pumping control is carried out, if without superpressure signal, detecting water pump 7
Whether there is stop signal;If the stop signal of water pump 7, then termination of pumping control is carried out, otherwise detect that hand opens pump signal:If hand is opened
Pump signal, then carry out increasing pump control;Then step Step3 is performed;Wherein, no superpressure signal, is represented when front tube presses parameter value
It is not above the safety value that water pipe can be born;There is hand to open pump signal, represent that there is artificial triggering starts water pump control key;There is stopping to believe
Number, represent that there is artificial triggering stops water pump control key;
Step2.2, if automatic mode, PLC1 then carries out the connection of frequency converter 2 and judges that frequency converter 2 has fault-free to deposit
:
Step2.2.1, when frequency converter 2 is faulty, then perform automatic power frequency constant pressure processing module:
Automatically the processing procedure of power frequency constant pressure processing module is:
Step2.2.1.1, pressure sensor 5 are by collection when front tube presses parameter value to carry out A/D through analog output module 4
It is sent to after conversion to PLC1;
Step2.2.1.2, PLC1 judge to work as front tube pressure parameter value whether in setting is interval through what A/D was changed:
If system mode is constant, then performs step Step3;
If not existing, the size interval with setting when front tube pressure parameter value changed through A/D is judged:If less than under interval
Limiting the sequentially power frequency that is then delayed increases the water pump number of a unlatching;Then it is delayed what sequentially reduction one was opened if greater than the interval upper limit
Water pump number, when the water pump 7 of work only remains one, then performs step Step3;
Step2.2.1.3, delay change hydraulic pressure setting range, and will work as front tube press parameter value SP1 passed through by pressure sensor 5
Analog output module 4 carry out A/D conversions after pass PLC1 back, meanwhile, set up pipe pressure parameter objectives value interval for [X11,
X12];Wherein, X11=SP-1.05 | △ p |, X12=SP+1.05 | △ p |, △ p=SP1-SP;
Step2.2.1.4, execution step Step2.2.1.2 interval according to the setting after renewal;
Wherein, for the first time into automatic power frequency constant pressure processing module when, set 1 pump working in power frequency state;
Step2.2.2, when 2 fault-free of frequency converter, whether PLC1 judges the frequency of frequency converter 2 in the range of setting:
If Step2.2.2.1, perform automatic frequency-conversion constant pressure processing module:
The processing procedure of automatic frequency-conversion constant pressure processing module is:
Step2.2.2.1.1, the collection of pressure sensor 5 work as front tube pressure parameter value and are used as the mould of feedback signal input converter 2
Intend input terminal;
Step2.2.2.1.2, the PID control by frequency converter 2, will work as front tube pressure parameter value and be made comparisons with SP:If big
In the reduction frequency of frequency converter 2 simultaneously drives the rotating speed of motor 8 of water pump 7 to reduce, if it is lower, frequency converter 2 improves frequency and drives water
The rotating speed of motor 8 of pump 7 is improved;
Step2.2.2.1.3, step Step2.2.2.1.1- step Step2.2.2.1.2 are repeated, until working as front tube
Press parameter value equal with SP, perform step Step3;
Wherein, when entering automatic frequency-conversion constant pressure processing module for the first time, open frequency converter 2 and 1 pump variable frequency zero-turn speed is opened
It is dynamic;
Step2.2.2.2, if it was not then performing in accordance with the following steps:
Step2.2.2.2.1, the collection of pressure sensor 5 work as front tube pressure parameter value and are used as the mould of feedback signal input converter 2
Intend input terminal;
Step2.2.2.2.2, the PID control by frequency converter 2, will work as front tube pressure parameter value and be made comparisons with SP:
Step2.2.2.2.2.1, if it is less, performing under-voltage processing module, the processing procedure of under-voltage processing module is:
Detect the presence of variable frequency pump operation:
If so, which pump variable frequency operation then judged, frequency conversion is changed to power frequency operation, step Step3 is performed;
If nothing, power frequency pump operation is detected the presence of:If so, then judge the power frequency operation which platform water pump is finally opened,
And start latter pump variable frequency operation of the water pump;If nothing, start a pump variable frequency operation, perform step Step3;
Step2.2.2.2.2.2, if it is greater, then performing superpressure processing module, the processing procedure of superpressure processing module is:
Detect the presence of variable frequency pump operation:
If so, which pump variable frequency operation then judged, variable frequency pump is turned off, step Step3 is performed;
If nothing, sequentially judge the power frequency operation which platform water pump is opened at first, close and start the pump frequency conversion after the water pump
Operation, performs step Step3;
Step3, fault detect:
If Step3.1, system jam, fault processing module is performed, fault processing module processing procedure is:
It is first determined whether water level deficiency or overfill:If not enough or overfill, closes whole system, while being transferred to alarm
Program sends water level signal alarm;
Next judge whether frequency converter 2 whether failure:If it is, closing automatic frequency-conversion constant pressure processing module, and start
Automatic power frequency constant pressure processing module, while being transferred to alert program sends frequency converter failure alarm;
The detection if Step3.2, system do not break down, then circulation performs the whole mistakes of step Step1 to Step3
Journey.
The present invention operation principle be:
Ensure the constant water consumption so as to ensure user at least favorable point of pressure supply of the delivery port of whole water supply webmaster
Satisfaction.
Multiple PLC, are connected by frequency conversion type constant-pressure water feeding system control system by PROFIBUS with upper monitoring main frame, then
By corresponding PLC1, other each underclad portions are connected, output signal and the phase of analog output module 4 that liquid level sensor 3 is detected
Connection, wherein:Changing value, is then converted into standard by the pressure change on the collection water system water outlet webmaster of pressure sensor 5
Electric signal, then this signal is respectively transmitted the PID modules to analog output module 4 and frequency converter 2.Frequency converter 2 is receiving
To after these signals, the processing of pid algorithm is carried out to it using PID modules, corresponding required control letter is finally changed into
Number --- frequency(This is adjusted for the speed to motor).Signal after frequency converter processing a, part is pre- as function
If value, and it is transmitted to PLC.PLC utilizes judgement and control of these signals to the switch of A.C. contactor group.PLC1 and frequency converter
2 PID modules are connected respectively to contactor switching circuit 6), contactor switching circuit 6)Directly it is connected with the pump group of motor 8, electricity
Machine 8 drives the operating of water pump 7 to supply water, and directly determines the running status of motor pump group.
Liquid level sensor 3 is mainly responsible for the water level depth of detection water supply pool, in most cases, and these signals are to make
Used for emergency measure.The signal of liquid level sensor 3 sends PLC1 to.Whether pond is judged according to this signal the purpose is to PLC1
In normal safety line, prevent from evacuating the danger overflowed with water by feed cistern and alarmed.
The input of the manual control signal of manual control module 9 is the operation for direct controlled motor pump group, and system exists
When under the pattern controlled manually, manual control signal(Including opening and stopping motor pump group)Passed through with highest priority
PLC directly controls the start and stop of water pump assembly.When the Automatic Control module that system switches, believed according to the input of each sensor
Number, signal just realizes the purpose of Isobarically Control automatically.Now, when frequency converter is working properly, pressure signal passes through pressure sensing
Device 5, sends the PID built in frequency converter 2 to, after PID arithmetic, and output signal controls the output frequency of frequency converter, so as to control
The rotating speed of water pump and then the pressure almost constant for keeping water supply line.When user's water consumption is big, webmaster loine pressure declines, frequency conversion
Device frequency is just raised, and pump rotary speed is accelerated, conversely, frequency declines water pump deceleration fortune surname, so as to maintain constant pressure water supply.Work as water consumption
More than water pump maximum output when, the control to contactor switching circuit is carried out by PLC1 internal control, makes it
A water pump is put into again.Same principle, PLC1 can automatically determine the water pump number of units of input according to the size of water consumption.
When frequency converter breaks down, system stops above-mentioned automatic water-supply mode, corresponding to start power frequency automatic running
Way of supplying water(The program is a kind of reserved regimen, and the system overwhelming majority time should all operate in frequency-changing pressure stabilizing operation side
Formula), now the signal of hydraulic pressure sensor directly input PLC1, by PLC1 carry out signal scope judge, so as to determine when increase
Pump(It can only be power frequency operation), when subtract pump.Thus approximate constant-pressure water feeding system is realized.
The real-time collection site data of upper monitoring main frame that are connected by PROFIBUS and field apparatus is supervised in real time
Control, realizes the purpose of constant pressure water supply.
Wherein, electric power system circuit is designed as:
[1] system carries out the conversion of voltage using transformer regulating function.Industrial power 380V/50Hz three-phase
The 220V power supplys that power conversion is required into PLC and other equipment.Certainly, the 380V's required frequency converter and water pump loop feature
Power supply, can be directly accessed by 380V power supplys.Certainly during access, using a total input-wire air switch(QF1)To ensure system
Safety.
[2] when in exterior power supply plant short supply interruption, system remains to maintain certain time, and system is not using herein
Uninterruptible power UPS measure.Charged state is in when UPS is flat, when system dead electricity, UPS can automatically switch to output state, dimension
The power supply of held controller
[3] to ensure the anti-interference function between electric power system, one will sufficiently consider the good earth of circuit, two
It is that the secondary concatenation connection of transformer will use twisted-pair feeder.Equipment also using several transformers respectively to required relevant voltage is entered
Row power supply, is so conducive to eliminating the influence between each power supply.
Field bus technique in the frequency conversion type constant-pressure water feeding system control system(PROFIBUS—DP)EM277
PROFIBUS-DP communication modules are used for S7-200 being connected to PROFIBUS-DP networks.EM277 is connected by DP COM1s
A main website in PROFIBUS-DP networks is connected to, S7-200CPU modules are connected to by serial i/O buses.System is used
PROFIBUS agreements are communicated by PROFIBUS bus network come the monitoring system with host computer.
The frequency conversion type constant-pressure water feeding system control system is calculated by correspondence parameter:The PLC1 is S7-200
CPU226 as system control unit;Model of pump of the water pump 7 from ChangNing Industry Co., Ltd, Beijing:
350S26;Motor model of the motor 8 from Fu'an City Yong Dasheng Electric Machine Co., Ltd:Y315M-4;According to selected motor
Capacity, frequency converter 2 selects model:MM430 frequency converters;Liquid of the liquid level sensor 3 from Jiangmen city Li De Electronics Co., Ltd.s
Level sensor model:LD600G A 1 – 3.5m – 5m;Pressure of the pressure sensor 5 from Deng Fang Shanghai Electronics Co., Ltd.
Sensor model number:JVPL 10;
Other aspect lime lights of system control thought:
[1] design of control system, need to consider that the operation number of units of water pump is controlled at 1 ~ 3 all the time when system is put into
In the range of(The need for design requirement).When the requirement of input exceedes this scope, it is desirable to which when pump is run or stopped, system is just entered
Progress of the row alarm with preventing which.This technical requirements is realized, as long as being supervised by the running status to motor pump group
Control, the limitation that system just can be to this progress water pump operation number of units.
[2] system lifetim, the life-span of the run time of particularly each motor and water pump are considered.In the present system, I
The opening sequence of each motor and water pump taken " first stop first to open, full cut-off first opens 1 " strategy;Equally stop their order just
It is the strategy of " first open and first stop ".Herein, realized by the way of inquiry.The thought that the mode of inquiry is realized is first to determine
The running status of each pump(Including variable frequency starting, power frequency startup, stop three kinds), then determined to open or stop water pump according to this
Number.
[3] power frequency constant pressure auto-controll operation mode is as a kind of alternative scheme, to prevent from stopping a hydraulic pressure in water pump
So-called switching not enough and that one hydraulic pressure overshoot of increase is caused is vibrated.Control system is using on-line identification hydraulic pressure control interval
Control program only crosses control interval systems and could acted, and water pump can just be switched over.The setting of control interval
Scheme:Assuming that current hydraulic pressure control interval is [X01 X02] X01<SP<X02.We can be set just when starting(That is program
When initializing assignment)Interval be [0.95SP, 1.05SP], SP be webmaster hydraulic pressure desired value.When webmaster hydraulic pressure exceedes this area
Between when, by certain delay.System starts action and (or increases or stop a water pump).After action, as front tube pressure signal SP1
By pressure sensor changed through A/D after pass PLC back, now then using SP be according to re-establishing control interval as [X11, X12], and
Value as the following formula:X11=SP-1.05 | △ p |, X12=SP+1.05 | △ p |, △ p=SP1-SP;
Therefore, system often carries out a pump switching, and hydraulic pressure control of PLC online modifications is interval to shake so as to avoid switching
Swing.
The beneficial effects of the invention are as follows:Using current more advanced variable-frequency control technique, pid control mode and PLC controls
Technology is carried out, to realize constant pressure water supply, has the advantages that good speed adjustment features, energy-saving effect are notable, operation process is safe and reliable.
Solve urbanite water consumption peak period and hydraulic pressure deficiency occur, the problem of low peak period hydraulic pressure is excessive realizes constant pressure water supply, obtain resource
Make full use of, reach the purpose of energy-conserving and environment-protective.Using field bus control system(FCS), open system, interchangeability, unification
Configuration, decentralised control improves the reliability, controllability and maintainability of system, and solves water factory's related process mistake in the future
The increase of the technological improvement of journey, the increase of the various live controlled plants of PROCESS FOR TREATMENT department, and field apparatus actual range, must
The problem of by the decentralization for greatly increasing whole system.By original many equipment access systems manually controlled, realize certainly
Dynamic control, greatly reduces the demand of personnel.Control system is using variable frequency water supply and power frequency two kinds of way of supplying water of water supply, it is ensured that
The normal water supply of special circumstances, ensures the normal domestic water of resident to greatest extent.
Brief description of the drawings
Fig. 1 is frequency conversion type constant pressure automatic control system principle of compositionality figure of the invention;
Fig. 2 is working-flow total figure of the invention;
Fig. 3 is manual handle block flow diagram of the invention;
Fig. 4 is automatic power frequency constant pressure processing module flow chart of the invention;
Fig. 5 is automatic frequency-conversion formula constant pressure processing module flow chart of the invention;
Fig. 6 is under-voltage processing module flow chart of the invention;
Fig. 7 is superpressure processing module flow chart of the invention;
Fig. 8 is fault processing module flow chart of the invention;
Fig. 9 is electric power system circuit diagram of the invention;
Figure 10 is contactor switching circuit schematic diagram of the invention;
Each label in figure:1-PLC;2- frequency converters;3- liquid level sensors;4- analog output modules;5- pressure sensors;
6- contactors;7- water pumps, 8- motors, 9- manual control modules, 10-PROFIBUS fieldbus, 11-PC ipc monitors system
System.
Embodiment
Embodiment 1:As Figure 1-10 shows, a kind of frequency conversion type constant-pressure water feeding system control system, including PLC1, frequency converter 2,
Liquid level sensor 3, analog output module 4, pressure sensor 5, contactor switching circuit 6, water pump 7, manually motor 8, control
Module 9;
The analog output module 4, frequency converter 2 and manual control module 9 are connected with PLC1 respectively, liquid level sensor
3 detection output signals be connected with analog output module 4, pressure sensor 5 detection output signal respectively with analog quantity
Output module 4 is connected with the PID modules of frequency converter 2, and the PID modules of PLC1 and frequency converter 2 are connected respectively to contactor switching
Circuit 6, contactor switching circuit 6 is connected with motor 8, and motor 8 drives the operating of water pump 7 to supply water.
Also include PROFIBUS fieldbus 10 and PC Monitor Computer Control Systems 11;Wherein, PC Monitor Computer Control Systems 11
It is connected by PROFIBUS fieldbus 10 with PLC1.
A kind of frequency conversion type constant-pressure water feeding system control method, methods described is comprised the following steps that:
Step1, the interval of pipe pressure parameter objectives value is set by PLC1 as [0.95SP, 1.05SP];
Step2, judge manual mode or automatic mode operation:
Step2.1, if manual mode, then start manual handle module 9:PLC1 detects liquid level sensor 3 whether there is
Water-level alarm signal;If water-level alarm signal, then termination of pumping control is carried out, if without water level alarm signal, detecting pressure
Sensor 5 whether there is superpressure signal;If superpressure signal, then termination of pumping control is carried out, if without superpressure signal, detecting water pump 7
Whether there is stop signal;If the stop signal of water pump 7, then termination of pumping control is carried out, otherwise detect that hand opens pump signal:If hand is opened
Pump signal, then carry out increasing pump control;Then step Step3 is performed;Wherein, no superpressure signal, is represented when front tube presses parameter value
It is not above the safety value that water pipe can be born;There is hand to open pump signal, represent that there is artificial triggering starts water pump control key;There is stopping to believe
Number, represent that there is artificial triggering stops water pump control key;
Step2.2, if automatic mode, PLC1 then carries out the connection of frequency converter 2 and judges that frequency converter 2 has fault-free to deposit
:
Step2.2.1, when frequency converter 2 is faulty, then perform automatic power frequency constant pressure processing module:
Automatically the processing procedure of power frequency constant pressure processing module is:
Step2.2.1.1, pressure sensor 5 are by collection when front tube presses parameter value to carry out A/D through analog output module 4
It is sent to after conversion to PLC1;
Step2.2.1.2, PLC1 judge to work as front tube pressure parameter value whether in setting is interval through what A/D was changed:
If system mode is constant, then performs step Step3;
If not existing, the size interval with setting when front tube pressure parameter value changed through A/D is judged:If less than under interval
Limiting the sequentially power frequency that is then delayed increases the water pump number of a unlatching;Then it is delayed what sequentially reduction one was opened if greater than the interval upper limit
Water pump number, when the water pump 7 of work only remains one, then performs step Step3;
Step2.2.1.3, delay change hydraulic pressure setting range, and will work as front tube press parameter value SP1 passed through by pressure sensor 5
Analog output module 4 carry out A/D conversions after pass PLC1 back, meanwhile, set up pipe pressure parameter objectives value interval for [X11,
X12];Wherein, X11=SP-1.05 | △ p |, X12=SP+1.05 | △ p |, △ p=SP1-SP;
Step2.2.1.4, execution step Step2.2.1.2 interval according to the setting after renewal;
Wherein, for the first time into automatic power frequency constant pressure processing module when, set 1 pump working in power frequency state;
Step2.2.2, when 2 fault-free of frequency converter, whether PLC1 judges the frequency of frequency converter 2 in the range of setting:
If Step2.2.2.1, perform automatic frequency-conversion constant pressure processing module:
The processing procedure of automatic frequency-conversion constant pressure processing module is:
Step2.2.2.1.1, the collection of pressure sensor 5 work as front tube pressure parameter value and are used as the mould of feedback signal input converter 2
Intend input terminal;
Step2.2.2.1.2, the PID control by frequency converter 2, will work as front tube pressure parameter value and be made comparisons with SP:If big
In the reduction frequency of frequency converter 2 simultaneously drives the rotating speed of motor 8 of water pump 7 to reduce, if it is lower, frequency converter 2 improves frequency and drives water
The rotating speed of motor 8 of pump 7 is improved;
Step2.2.2.1.3, step Step2.2.2.1.1- step Step2.2.2.1.2 are repeated, until working as front tube
Press parameter value equal with SP, perform step Step3;
Wherein, when entering automatic frequency-conversion constant pressure processing module for the first time, open frequency converter 2 and 1 pump variable frequency zero-turn speed is opened
It is dynamic;
Step2.2.2.2, if it was not then performing in accordance with the following steps:
Step2.2.2.2.1, the collection of pressure sensor 5 work as front tube pressure parameter value and are used as the mould of feedback signal input converter 2
Intend input terminal;
Step2.2.2.2.2, the PID control by frequency converter 2, will work as front tube pressure parameter value and be made comparisons with SP:
Step2.2.2.2.2.1, if it is less, performing under-voltage processing module, the processing procedure of under-voltage processing module is:
Detect the presence of variable frequency pump operation:
If so, which pump variable frequency operation then judged, frequency conversion is changed to power frequency operation, step Step3 is performed;
If nothing, power frequency pump operation is detected the presence of:If so, then judge the power frequency operation which platform water pump is finally opened,
And start latter pump variable frequency operation of the water pump;If nothing, start a pump variable frequency operation, perform step Step3;
Step2.2.2.2.2.2, if it is greater, then performing superpressure processing module, the processing procedure of superpressure processing module is:
Detect the presence of variable frequency pump operation:
If so, which pump variable frequency operation then judged, variable frequency pump is turned off, step Step3 is performed;
If nothing, sequentially judge the power frequency operation which platform water pump is opened at first, close and start the pump frequency conversion after the water pump
Operation, performs step Step3;
Step3, fault detect:
If Step3.1, system jam, fault processing module is performed, fault processing module processing procedure is:
It is first determined whether water level deficiency or overfill:If not enough or overfill, closes whole system, while being transferred to alarm
Program sends water level signal alarm;
Next judge whether frequency converter 2 whether failure:If it is, closing automatic frequency-conversion constant pressure processing module, and start
Automatic power frequency constant pressure processing module, while being transferred to alert program sends frequency converter failure alarm;
The detection if Step3.2, system do not break down, then circulation performs the whole mistakes of step Step1 to Step3
Journey.
Embodiment 2:As Figure 1-10 shows, a kind of frequency conversion type constant-pressure water feeding system control system, including PLC1, frequency converter 2,
Liquid level sensor 3, analog output module 4, pressure sensor 5, contactor switching circuit 6, water pump 7, manually motor 8, control
Module 9;
The analog output module 4, frequency converter 2 and manual control module 9 are connected with PLC1 respectively, liquid level sensor
3 detection output signals be connected with analog output module 4, pressure sensor 5 detection output signal respectively with analog quantity
Output module 4 is connected with the PID modules of frequency converter 2, and the PID modules of PLC1 and frequency converter 2 are connected respectively to contactor switching
Circuit 6, contactor switching circuit 6 is connected with motor 8, and motor 8 drives the operating of water pump 7 to supply water.
A kind of frequency conversion type constant-pressure water feeding system control method, methods described is comprised the following steps that:
Step1, the interval of pipe pressure parameter objectives value is set by PLC1 as [0.95SP, 1.05SP];
Step2, judge manual mode or automatic mode operation:
Step2.1, if manual mode, then start manual handle module 9:PLC1 detects liquid level sensor 3 whether there is
Water-level alarm signal;If water-level alarm signal, then termination of pumping control is carried out, if without water level alarm signal, detecting pressure
Sensor 5 whether there is superpressure signal;If superpressure signal, then termination of pumping control is carried out, if without superpressure signal, detecting water pump 7
Whether there is stop signal;If the stop signal of water pump 7, then termination of pumping control is carried out, otherwise detect that hand opens pump signal:If hand is opened
Pump signal, then carry out increasing pump control;Then step Step3 is performed;Wherein, no superpressure signal, is represented when front tube presses parameter value
It is not above the safety value that water pipe can be born;There is hand to open pump signal, represent that there is artificial triggering starts water pump control key;There is stopping to believe
Number, represent that there is artificial triggering stops water pump control key;
Step2.2, if automatic mode, PLC1 then carries out the connection of frequency converter 2 and judges that frequency converter 2 has fault-free to deposit
:
Step2.2.1, when frequency converter 2 is faulty, then perform automatic power frequency constant pressure processing module:
Automatically the processing procedure of power frequency constant pressure processing module is:
Step2.2.1.1, pressure sensor 5 are by collection when front tube presses parameter value to carry out A/D through analog output module 4
It is sent to after conversion to PLC1;
Step2.2.1.2, PLC1 judge to work as front tube pressure parameter value whether in setting is interval through what A/D was changed:
If system mode is constant, then performs step Step3;
If not existing, the size interval with setting when front tube pressure parameter value changed through A/D is judged:If less than under interval
Limiting the sequentially power frequency that is then delayed increases the water pump number of a unlatching;Then it is delayed what sequentially reduction one was opened if greater than the interval upper limit
Water pump number, when the water pump 7 of work only remains one, then performs step Step3;
Step2.2.1.3, delay change hydraulic pressure setting range, and will work as front tube press parameter value SP1 passed through by pressure sensor 5
Analog output module 4 carry out A/D conversions after pass PLC1 back, meanwhile, set up pipe pressure parameter objectives value interval for [X11,
X12];Wherein, X11=SP-1.05 | △ p |, X12=SP+1.05 | △ p |, △ p=SP1-SP;
Step2.2.1.4, execution step Step2.2.1.2 interval according to the setting after renewal;
Wherein, for the first time into automatic power frequency constant pressure processing module when, set 1 pump working in power frequency state;
Step2.2.2, when 2 fault-free of frequency converter, whether PLC1 judges the frequency of frequency converter 2 in the range of setting:
If Step2.2.2.1, perform automatic frequency-conversion constant pressure processing module:
The processing procedure of automatic frequency-conversion constant pressure processing module is:
Step2.2.2.1.1, the collection of pressure sensor 5 work as front tube pressure parameter value and are used as the mould of feedback signal input converter 2
Intend input terminal;
Step2.2.2.1.2, the PID control by frequency converter 2, will work as front tube pressure parameter value and be made comparisons with SP:If big
In the reduction frequency of frequency converter 2 simultaneously drives the rotating speed of motor 8 of water pump 7 to reduce, if it is lower, frequency converter 2 improves frequency and drives water
The rotating speed of motor 8 of pump 7 is improved;
Step2.2.2.1.3, step Step2.2.2.1.1- step Step2.2.2.1.2 are repeated, until working as front tube
Press parameter value equal with SP, perform step Step3;
Wherein, when entering automatic frequency-conversion constant pressure processing module for the first time, open frequency converter 2 and 1 pump variable frequency zero-turn speed is opened
It is dynamic;
Step2.2.2.2, if it was not then performing in accordance with the following steps:
Step2.2.2.2.1, the collection of pressure sensor 5 work as front tube pressure parameter value and are used as the mould of feedback signal input converter 2
Intend input terminal;
Step2.2.2.2.2, the PID control by frequency converter 2, will work as front tube pressure parameter value and be made comparisons with SP:
Step2.2.2.2.2.1, if it is less, performing under-voltage processing module, the processing procedure of under-voltage processing module is:
Detect the presence of variable frequency pump operation:
If so, which pump variable frequency operation then judged, frequency conversion is changed to power frequency operation, step Step3 is performed;
If nothing, power frequency pump operation is detected the presence of:If so, then judge the power frequency operation which platform water pump is finally opened,
And start latter pump variable frequency operation of the water pump;If nothing, start a pump variable frequency operation, perform step Step3;
Step2.2.2.2.2.2, if it is greater, then performing superpressure processing module, the processing procedure of superpressure processing module is:
Detect the presence of variable frequency pump operation:
If so, which pump variable frequency operation then judged, variable frequency pump is turned off, step Step3 is performed;
If nothing, sequentially judge the power frequency operation which platform water pump is opened at first, close and start the pump frequency conversion after the water pump
Operation, performs step Step3;
Step3, fault detect:
If Step3.1, system jam, fault processing module is performed, fault processing module processing procedure is:
It is first determined whether water level deficiency or overfill:If not enough or overfill, closes whole system, while being transferred to alarm
Program sends water level signal alarm;
Next judge whether frequency converter 2 whether failure:If it is, closing automatic frequency-conversion constant pressure processing module, and start
Automatic power frequency constant pressure processing module, while being transferred to alert program sends frequency converter failure alarm;
The detection if Step3.2, system do not break down, then circulation performs the whole mistakes of step Step1 to Step3
Journey.
Embodiment 3:As Figure 1-10 shows, a kind of frequency conversion type constant-pressure water feeding system control system, including PLC1, frequency converter 2,
Liquid level sensor 3, analog output module 4, pressure sensor 5, contactor switching circuit 6, water pump 7, manually motor 8, control
Module 9;
The analog output module 4, frequency converter 2 and manual control module 9 are connected with PLC1 respectively, liquid level sensor
3 detection output signals be connected with analog output module 4, pressure sensor 5 detection output signal respectively with analog quantity
Output module 4 is connected with the PID modules of frequency converter 2, and the PID modules of PLC1 and frequency converter 2 are connected respectively to contactor switching
Circuit 6, contactor switching circuit 6 is connected with motor 8, and motor 8 drives the operating of water pump 7 to supply water.
Also include PROFIBUS fieldbus 10 and PC Monitor Computer Control Systems 11;Wherein, PC Monitor Computer Control Systems 11
It is connected by PROFIBUS fieldbus 10 with PLC1.
Embodiment 4:As Figure 1-10 shows, a kind of frequency conversion type constant-pressure water feeding system control system, including PLC1, frequency converter 2,
Liquid level sensor 3, analog output module 4, pressure sensor 5, contactor switching circuit 6, water pump 7, manually motor 8, control
Module 9;
The analog output module 4, frequency converter 2 and manual control module 9 are connected with PLC1 respectively, liquid level sensor
3 detection output signals be connected with analog output module 4, pressure sensor 5 detection output signal respectively with analog quantity
Output module 4 is connected with the PID modules of frequency converter 2, and the PID modules of PLC1 and frequency converter 2 are connected respectively to contactor switching
Circuit 6, contactor switching circuit 6 is connected with motor 8, and motor 8 drives the operating of water pump 7 to supply water.
Embodiment 5:As Figure 1-10 shows, a kind of frequency conversion type constant-pressure water feeding system control method, the specific step of methods described
It is rapid as follows:
Step1, the interval of pipe pressure parameter objectives value is set by PLC1 as [0.95SP, 1.05SP];
Step2, judge manual mode or automatic mode operation:
Step2.1, if manual mode, then start manual handle module 9:PLC1 detects liquid level sensor 3 whether there is
Water-level alarm signal;If water-level alarm signal, then termination of pumping control is carried out, if without water level alarm signal, detecting pressure
Sensor 5 whether there is superpressure signal;If superpressure signal, then termination of pumping control is carried out, if without superpressure signal, detecting water pump 7
Whether there is stop signal;If the stop signal of water pump 7, then termination of pumping control is carried out, otherwise detect that hand opens pump signal:If hand is opened
Pump signal, then carry out increasing pump control;Then step Step3 is performed;Wherein, no superpressure signal, is represented when front tube presses parameter value
It is not above the safety value that water pipe can be born;There is hand to open pump signal, represent that there is artificial triggering starts water pump control key;There is stopping to believe
Number, represent that there is artificial triggering stops water pump control key;
Step2.2, if automatic mode, PLC1 then carries out the connection of frequency converter 2 and judges that frequency converter 2 has fault-free to deposit
:
Step2.2.1, when frequency converter 2 is faulty, then perform automatic power frequency constant pressure processing module:
Automatically the processing procedure of power frequency constant pressure processing module is:
Step2.2.1.1, pressure sensor 5 are by collection when front tube presses parameter value to carry out A/D through analog output module 4
It is sent to after conversion to PLC1;
Step2.2.1.2, PLC1 judge to work as front tube pressure parameter value whether in setting is interval through what A/D was changed:
If system mode is constant, then performs step Step3;
If not existing, the size interval with setting when front tube pressure parameter value changed through A/D is judged:If less than under interval
Limiting the sequentially power frequency that is then delayed increases the water pump number of a unlatching;Then it is delayed what sequentially reduction one was opened if greater than the interval upper limit
Water pump number, when the water pump 7 of work only remains one, then performs step Step3;
Step2.2.1.3, delay change hydraulic pressure setting range, and will work as front tube press parameter value SP1 passed through by pressure sensor 5
Analog output module 4 carry out A/D conversions after pass PLC1 back, meanwhile, set up pipe pressure parameter objectives value interval for [X11,
X12];Wherein, X11=SP-1.05 | △ p |, X12=SP+1.05 | △ p |, △ p=SP1-SP;
Step2.2.1.4, execution step Step2.2.1.2 interval according to the setting after renewal;
Wherein, for the first time into automatic power frequency constant pressure processing module when, set 1 pump working in power frequency state;
Step2.2.2, when 2 fault-free of frequency converter, whether PLC1 judges the frequency of frequency converter 2 in the range of setting:
If Step2.2.2.1, perform automatic frequency-conversion constant pressure processing module:
The processing procedure of automatic frequency-conversion constant pressure processing module is:
Step2.2.2.1.1, the collection of pressure sensor 5 work as front tube pressure parameter value and are used as the mould of feedback signal input converter 2
Intend input terminal;
Step2.2.2.1.2, the PID control by frequency converter 2, will work as front tube pressure parameter value and be made comparisons with SP:If big
In the reduction frequency of frequency converter 2 simultaneously drives the rotating speed of motor 8 of water pump 7 to reduce, if it is lower, frequency converter 2 improves frequency and drives water
The rotating speed of motor 8 of pump 7 is improved;
Step2.2.2.1.3, step Step2.2.2.1.1- step Step2.2.2.1.2 are repeated, until working as front tube
Press parameter value equal with SP, perform step Step3;
Wherein, when entering automatic frequency-conversion constant pressure processing module for the first time, open frequency converter 2 and 1 pump variable frequency zero-turn speed is opened
It is dynamic;
Step2.2.2.2, if it was not then performing in accordance with the following steps:
Step2.2.2.2.1, the collection of pressure sensor 5 work as front tube pressure parameter value and are used as the mould of feedback signal input converter 2
Intend input terminal;
Step2.2.2.2.2, the PID control by frequency converter 2, will work as front tube pressure parameter value and be made comparisons with SP:
Step2.2.2.2.2.1, if it is less, performing under-voltage processing module, the processing procedure of under-voltage processing module is:
Detect the presence of variable frequency pump operation:
If so, which pump variable frequency operation then judged, frequency conversion is changed to power frequency operation, step Step3 is performed;
If nothing, power frequency pump operation is detected the presence of:If so, then judge the power frequency operation which platform water pump is finally opened,
And start latter pump variable frequency operation of the water pump;If nothing, start a pump variable frequency operation, perform step Step3;
Step2.2.2.2.2.2, if it is greater, then performing superpressure processing module, the processing procedure of superpressure processing module is:
Detect the presence of variable frequency pump operation:
If so, which pump variable frequency operation then judged, variable frequency pump is turned off, step Step3 is performed;
If nothing, sequentially judge the power frequency operation which platform water pump is opened at first, close and start the pump frequency conversion after the water pump
Operation, performs step Step3;
Step3, fault detect:
If Step3.1, system jam, fault processing module is performed, fault processing module processing procedure is:
It is first determined whether water level deficiency or overfill:If not enough or overfill, closes whole system, while being transferred to alarm
Program sends water level signal alarm;
Next judge whether frequency converter 2 whether failure:If it is, closing automatic frequency-conversion constant pressure processing module, and start
Automatic power frequency constant pressure processing module, while being transferred to alert program sends frequency converter failure alarm;
The detection if Step3.2, system do not break down, then circulation performs the whole mistakes of step Step1 to Step3
Journey.
Above in conjunction with accompanying drawing to the present invention embodiment be explained in detail, but the present invention be not limited to it is above-mentioned
Embodiment, can also be before present inventive concept not be departed from the knowledge that those of ordinary skill in the art possess
Put that various changes can be made.